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Martyn... I understand you're being a little tired of having to replace, set dwell and adjust timing periodically, when an electronic conversion basically eliminates this chore. The good thing about points is that when the system needs attention, it usually warns you by a progressive fall-off in performance. An electronic conversion is usually "on" or "off" in terms of failure... usually no warning. And of course, don't forget the dizzy needs a few drops of oil every now and then! The forgoing having been said, I've used Crane "700" and "3000" units up until a couple of years ago,... MORE
The typical function of a resistor in either the coil as in built in, special resistance wire to the coil or with one in series between the power supply and the coil is this. When the resistor is cold, it passes a lot of current so the cooil will have about full voltage at start up to produce a hot spark. As the resistor heats up, it reduces the amount of power getting through, so instead of a full 12 volts, for example, it now is passing only 9 volts or so. The coil will still produce a full... MORE
It is election day in Canada today. For some real excitment, tune in. It may be all over by noon by what happens in the east. However us in BC hope to show a little clout later in the day. We'll be able to know what is happening in the east starting at 3:30 our time. With polls closing at 7:00 we could hold the key to how the government looks at the end of the day. Here's hoping. Have a good one. Ian "mcalpine" 32789... MORE
I'm getting ready to rebuild my 79's MC, as it keeps dripping brake fluid on my foot. Any special words of advice from someone who's done it? Are there any things I should be especially aware of, or any special precautions to take? Thanks in advance, George "chuibuddy" 32784... MORE
Yep.... You got it big guy!!!! Of course, this assumes a reasonably healthy engine pulling decent vacuum. TWO CAVEATS.... 1) If the engine's clapped out and is pullin' lousy vacuum, the pistons will never "top out", spring tension and fully open butterflies notwithstanding and thus....it follows, that.... 2) the entire induction system has got to be "air tight" as well. You don't need a midget under the hood. You need an SU carb tool kit!!! It comes with a little jet centering tool along with "rods" you place within the piston tubes which temporarily take the place of the... MORE
Rob, That helps. So let me get more clear. The spring rate (color) determines how high the piston will rise in relation to redline under load, for example if it will not reach the top under load or it reaches the top way before red line under load, it is a function of the spring/color and how fast the piston reacts (not how high it goes) is a function of the viscosity of the oil in the damper. Is that close? Now all we need is a midget to curl up in the engine bay and peer into the... MORE
Guys... Can't help but believe we are losing something in the translation, here. A faster rising of the piston (as Duncan points out) can be counterproducive to acceleration in terms of low end torque not only because of the "ramming affect" of a "smaller" venturi at the low end, but also because of the "leaning out" of the mixture on acceleration caused by "too great a rate". The thing is, the "proper weight" oil is "correct" for "rate of rise" in accordance with the maker's design of the application to begin with. The spring controls wherein the needle will... MORE
You know...this is a helluva good letter, RBH, IMHO. I think I will send this on to Bill O'Reilly at Fox news "for his information". I am apolitical though generally interested and frankly believe Kerry is "there" simply because Hillary is planned for the future. Frankly, I more respect Lieberman but his "timing" is bad due to global circumstances beyond anyone's control. Cap'n. Bob '60 :{) PilotRob@... 32734... MORE
"venturi", Bob! :):) Call it whatever you will...as long as we're all on the same page in the same book! :) I like Alan's suggestion as to the British MG Metro SU carb. set-up alternative to Jen's carb. problem. The stock Metro needle would probably be right in the ballpark as well, considering the Metro is an 80hp Series A. Good one, this...methinks. Cap'n. Bob '60 :{) PilotRob@... 32727... MORE
Cap'n , Personally I've never heard it called an air valve - always a piston. I have a dim recollection that one of the tuning mods for improved acceleration was to drill two 1/82 (3.125 mm) holes in the piston at 90 degrees to the keyway. The existing hole in the side of the piston would be tapped and an aluminium plug screwed in .That was for the HS2 1 1/4" carb for minis though - might work on the midgets also. Somebody will prolly have an SU tuning book and confirm or deny the above. Just my tuppenyworth... MORE
Boy! You got that right at tune up!!! Paul A "Paul Asgeirsson" 32715... MORE
Hi, Just ran my Bugeye in 4 Vintage races but fortunately blew a head gasket, cutting short my last race, because the master cylinder had suddenly lost about half its fluid in a few laps! Guess now is the time to upgrade to a dual circuit cylinder. What is the easiest route to do this? Any "how to" guides on the internet? There is a roll cage tube that goes quite close beside the "box" the master brake/clutch cylinder unit is in, so I don't have a lot of room for anything. Is there a later spridget dual brake/clutch... MORE
OH...and Jens...I forgot!!! Before you get started on a compression check, DO check the throttle cable hookup and be sure when you put the accelerator pedal fully to the floor the BUTTERFLY is FULLY open! :):) Cap'n. Bob '60 :{) PilotRob@... 32706... MORE
Ah HAH.... You may have hit the nail right on the head here, Jens... "If (my engine...tuned or not) cannot SUCK (produce enough vacuum) to open a pair of HS2's....." EXACTLY!!!! It is time to "begin at the beginning", Jens. As in MAJOR tune-up. Step one is checking engine "mechanical health".... with valves properly adjusted...time for a basic compression & leakdown check. Considering recency of engine work, you're looking for 150 or better on compression check and leak-down rates of less than 10%. Remember to hold the butterflies fully open (accelerator pedal fully to the floor) during the compression... MORE
Jens... ...the air valve is the largest moveable part of the SU carb and holds the needle. I have heard people refer to the air valve as a "piston". The butterfly (or it's position) is controlled by your foot and the accelerator cable and is the closest moveable part of the carb closest to the intake manifold. :):) Cap'n. Bob '60 :{) PilotRob@... 32704... MORE
Jens Fixed and 'spring loaded' needles are not interchangeable, as the spring loaded needle has a collar attached and is longer than the fixed type. My SU Needle Sizes chart shows me that AAV is indeed a 'spring loaded' needle for a .090" jet. I'm not even sure any HS2's used 'spring loaded' needles, but I'm not sure on that one. N "amukdigiphoto" 32691... MORE
Jens, Fixed needles are held rigidly by a grub screw into the piston, but swinging (or biased spring) needles are retained by a separate collar, they are forced by a light spring so that they contact one side of the jet, so no centering is needed, but the jet and needle both wear more than the fixed type. They're not interchangeable because of the retaining ring on the spring type. HS2s used both types, depending on the year. You can check which yours is by the tag number on the carb float bowl (what do you mean, it's not... MORE
The Purpose of Tools HAMMER: Originally employed as a weapon of war, the hammer nowadays is used as a kind of divining rod to locate expensive parts not far from the object we are trying to hit. MECHANIC'S KNIFE: Used to open and slice through the contents of cardboard cartons delivered to your front door; works particularly well on boxes containing leather goods. ELECTRIC HAND DRILL: Normally used for spinning steel Pop rivets in their holes until you die of old age. PLIERS: Used to round off bolt heads. HACKSAW: One of a family of cutting tools built on... MORE
I have recently acquired a 'new, old stock' crankshaft rear oil-seal kit for an A-series engine, but it did not come with any fitting instructions. Although it looks fairly simple, I want to make sure that everything is fitted correctly, so I wondered if anyone has fitted this kit and still has the fitting instructions? If so, would it be possible to scan or otherwise reproduce? All replies welcome. Thanks in advance Dave "daveo138" 32688... MORE
Willliam, FWIW-I bought an 1975 for $500 and have replaced virtually every mechanical component. I found and freshly rebuilt engine through the MG Club of Chicagoland classifieds for $632 (engine and freight). It need a backplate and dizzy which I pirated from the original. The special designation to the best of my knowledge had little to do with performance and a lot to do with creature comfort ...radio, carpet appearance package etc. My estimation is that the $600 is OK but you'll need to do more than you think. It will take longer and cost more. Rob C 1975... MORE
I'm looking at buying a 1976 MG Midget special 57K with the 1500cc engine it has the Webber carb upgrade new starter and alternator but the connecting rod bolt came out and trashed the lower end of the engine they said it need a crank connecting rod and the block needed to be machined. How much would it cost to rebuild vs. replace with new/used engines???? also what are the specs for this engine stock and with the Webber carb kit??? besides that the car is decent shape minor rust (not bad surface only on seams)and there are a... MORE
I've just fited a 73 Midget motor into my 67 Morris Minor. The smog rails etc have been removed and the ports plugged. Curently, the induction is the stock Minor setup, this will chnage in time, but I want to get the car finished before I go dual carbs and a larger bore exhaust. Anyway, I have 4 distributors, the stock 41400 25D unit, the stock 67 Minor unit, opne from a 64 TR4 and a DM2 from God know what. As far as I can tell *none* of the 4 vacuum advances work. I have removed each and... MORE
Rich... Your fuel pressure setting is correct. There is some falling off in pressure between pump and carb. I've been using low pressure (2.5-4.0) Facets for many moons now with stock float valves...no problems. Same with previous Vizardized Series A with 90hp to rear wheels and Weber "45" except pump was Facet 6psi or so through 2.5 pressure regulator. Stock float valves in this case also. No problems. What pressure does your pump initially put out? What "color" would appear on a NEW set of spark plugs on your car after a hard run, preferably up a reasonably sloped... MORE
I thought 1.5-2 psi was optimal for the SUs and anything more would be a problem (of course every car has its own quirks). I have my regulator set around 2 psi (WAG). However by my seat of the pants I have a funny feeling that during high speed extended runs it "feels" like it stumbles just a bit. I haven't tried bumping up the pressure just yet. I am thinking fuel starvation due to slightly to pressure being a bit low. When I first installed and set the regulator it was way too low and the rear carb... MORE
Hi, Peter... I am no 1500 guy but I've been following the thread on the discussion of longer studs needed for certain valve covers produced for the 1500 Spit motor. I just came across something in my TriumphTune performance manual which apparently deals with this. TriumphTune (TT) Part #105123 "On late 1500 models after '78, longer studs will be required wherein tube nuts are fitted as standard" This pertains to valve covers, all using the standard gasket. Sounds like what you may be looking for? Cap'n. Bob '60 :{) PilotRob@... 32602... MORE
